Glaucoma is one of the leading causes of adult blindness, and visual impairment in glaucoma is irreversible. Therefore, it is desired that the diagnosis of glaucoma and the observation of the progression thereof be properly carried out. OCT techniques for forming an image representing the surface morphology and the internal morphology of a measurement object by using a light beam from a laser light source or the like are useful for the diagnosis of glaucoma and the like. For example, with reference to an image of the fundus formed by using OCT, changes in the morphology of the retina can be observed. Thus, the progression of glaucoma, the posttreatment condition, and the like can be observed.
In the diagnosis of glaucoma and the like, it is considered to be important to focus attention on changes in the morphology of the optic disc and that of the retinal nerve fiber layer. As to the optic disc, the shape and size are of interest, and the inclination of the optic disc, and the shape and size of C (Cup), D (Disc), and R (Rim) and the like are used for diagnostic materials. Meanwhile, as to the retinal nerve fiber layer, the thickness, loss, and the like are used for diagnostic materials. In addition to these, in recent years, as contributing to the early detection of glaucoma, the morphology of the lamina cribrosa has been attracting attention. The lamina cribrosa is a mesh-like tissue in which a plurality of holes is formed where the optic nerves in the optic disc pass through.
For example, the patent document 1 discloses the analysis of a lamina cribrosa region. Specifically, the patent document 1 discloses a method of detecting the lamina cribrosa region from a tomographic image obtained by using OCT and of analyzing a lamina cribrosa region.